I have a relatively simple question or two . I am shopping for some used cars , GM naturally since I am a life time GM guy . I just purchased a 1991 Buick Park Avenue , in fact I don’t have it yet . I paid for it and it’* going to be shipped this coming week . The car is a one owner with 21,000 miles on it and looks like new . I did some research on the reliability of that year and it looked good so I gave them my debit card and should have it directly . But I’m still looking for maybe 2 more cars , and that’* why I’m here . On these Buicks with the plastic intakes leaking , I think from 1996 to 2005 ? I have a chance to get one (2003 Century LS) with very low miles . My question is , is there any thing I can do to this car to prevent a this problem from happening later on . Or should I just avoid these years ? I know these are good little cars , I actually feel lucky to have found the Park Avenue .

What ever advise you more experienced can give will be much appreciated , and by the way I am not a mechanic . I’m better than most non mechanics , but still not very good at it .

TheReaper!

Truth be told, the 96-05 3.8 V6 will have the UIM issues you describe. There is really now way to prevent the issue without preemptively repairing it. Once it is addressed however, reliability is a very strong suit.

The Century you speak of should have a 3.1 V6, which doesn't suffer from the same problems, however they have their own set of problems, which can be addressed, however I believe reliability is not quite what the 3.8 is (but not awful either). I wouldn't avoid the 3.8 because of it however, because once that is addressed, it'* fixed, and if fixed right, shouldn't need to be addressed again for quite some time ($750ish repair if taken in)

I look forward to seeing more on that Park Avenue, but that few miles always puts me on edge. Take it easy on it and gradually get the legs stretched on it, and it should treat you very well.

According to car-complaints.com this car also has intake problems , but you are right it does have the smaller engine .
2003 Buick Century Intake Manifold Gasket Leak: 10 Complaints

TheReaper!

True, the 3.8, as well as the 3.1/3.4 do have LIM gasket problems as well, not to be confused with the 'plastic manifold' issues of the 3.8.

From what I understand, the 3.1/3.4 will start losing coolant (into the crankcase usually) which can lead to warped or cracked heads (Iron block, aluminum heads if memory serves), essentially major engine work. The 3.8 is solid cast iron construction, with an aluminum lower manifold, and plastic upper. As long is the oil is not compromised, there is usually not any concern if the issue is addressed at the first sign of coolant loss, or even before.

From what I've read on the 3.1 it'* the lower intake gasket that gets eaten up by Dexcool anti freeze ?

TheReaper!

the original gaskets all plastic and rubber and over time the plastic fails, on the 3.1/3.4 it will take out the head gaskets. the 3.8 is a brick shithouse so the head gaskets almost never go unless you have a real bad coolant leak and let it go for a while. i would rather have 96+ 3800. the early ones like your pa have that expensive and problematic magnovox icm and abs. the newer PA/lesabre ones rarely fail and are cheap to fix. i have done a few of the updates but my inlaws 00 lesabre was maybe 120-130, for aluminum gaskets, aluminum coolant elbow, dorman 3800 upgrade kit that comes thicker upper and redesigned egr. thats all the issues you will have. would not buy any century size vehicle they are a terrible pain to work on and stuff breaks all the time.

What kind of expense should one expect with Magnavox icm and abs , and when are they likely to go bad (miles) ? I've read quite a bit of reviews on the 1991 PA I just bought and it got high marks from the owners .

TheReaper!

If any one has some ideas on a better more reliable car I would love the hear them . The reason I am looking at the older Buicks is we had some in the family before , and they were very reliable . In fact my son had one and said while the car got very old and very ugly , it just wouldn't quit . Right now I am searching the country side for that little grandma Buick that was hardly ever driven , but like I said .........got a better idea lay it on me .

TheReaper!

If you could find a low mileage Riviera, 1999 was the last year they made them....they we a solid car with no rattles.....just a two door(never had a 4 door).....get the SC'd engine and you don't have the upper plenum problem....

This model was from 1995 to 1999.....'97 got a beefier tranny.....

With the SC'd engine, this car had plenty of get up......would get over 39mpg in the highway....it was a solid ride......If they had made a 4 door version, like the Aurora, it would have sold more cars, but GM was trying to help the sales of Oldsmobile....

Also the P/A'*, LeSabres(limited), and Bonnevilles(SLE, SSEi) we good vehicles....

The ICM can go at any time, given the age. If it'* still running fine, there is no point in messing with it. The complete ICM/ Coil setup can be swapped with a newer style unit that used the 3 individual coils, from a 92-93 model year series 1 engine.

As for the ABS, the ones from 1990 and before were fully hydraulic (teves), and prohibitively expensive to repair (replacement hydraulic unit is literally $1k on Rockauto). Rockauto lists the same system for '91-'93 however, which has served me well, and appears to be a much more reasonable setup. It'* not something to really worry about, but if an issue arises with it, it can be addressed then.

There are literally thousands of nitpicks on the car that we can scare you to death with, but it'* best to handle it as it comes usually. If something does crop up, we are happy to help share any information you need.

I agree with the bullet proof nature of the 3.8 v6 however. It takes quite a bit to kill one typically.

There is another warning I would also like to share in your journeys, OBD 1.5. It is typically found in 94-95 model year vehicles, and requires scanners that are specifically compatible with it, which can make for tricky diagnostics if you are at the mercy of someone else for repairs. It'* not necessarily a deal breaker every time, but should be given thought to when deciding whether or not to buy it.

Also, it seems that as the 2000+ models age, they tend to have more 'model specific' issues that crop up too, especially with high mileage. Little things like window regulators, wheel hubs, etc.